Electronic device for automatic indication,registration and forecast of local and distant thunderstorms



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ELECTRONIC DEVICE FOR AUTOMATlC .[NDLCATIOI], REGISTRATION AND FORECAST OF LOCAL AND DISTANT THUNDERSTORMS Filed Dec. 14, 1966 2 Sheets-Sheet l T'ENDENC v TO THUNDERSTORM Fig.2

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Sept. 2, 1969 HElNZ-JURGEN FISCHER ET AL 3,46 7 ELECTRONIC DEVICE FOR AUTOMATIC INDICATION. REGISTRATION AND FORECAST OF LOCAL AND DISTANT THUNDERSTORMS Filed Dec. 14. 1966 2 Sheets-Sheet 2 WI HW H547 Iii/5014770 Fig, 4

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United States Patent 3,465,245 ELECTRONIC DEVICE FOR AUTOMATIC INDICA- TION, REGISTRATION AND FORECAST OF LOCAL AND DISTANT THUNDERSTORMS Heinz-Jurgen Fischer, Elisabethenstrasse 2, Ravensburg, Germany, and Walter Schmidt, Badstrasse 16 /5, Lindau-Enzisweiler, Germany Filed Dec. 14, 1966, Ser. No. 601,674 Claims priority, application Germany, Dec. 15, 1965, A 51,124; Oct. 12, 1966, A 53,799 Int. Cl. G01r 31/02 US. Cl. 32472 18 Claims ABSTRACT OF THE DISCLOSURE An electronic device for automatic indication, registration and forecasting of local and distant thunderstorms, whereby a part of a signal emitted from lightning flashes is received by means of a ferrite antenna. The signal is amplified by means of a resonance amplifier, whereupon the signal is threefold exploited and in particular: 1) relating to the intensity of the lightning flash; (2) in relation to the lightning flashes during a time unit; and (3) relative to the time duration, in which during a time interval total lightning disturbances occur.

The present invention relates to an apparatus having for its purpose a widespread practical use for indicating, registering and forecasting local and distant thunderstorms, particularly allowing to judge the tendency to thunderstorms by a supplementary information and to warn in time particularly endangered locations.

An assertion about the existence of local and distant thunderstorms is made-according to the present state of scientific knowledge-preferably by means of so-called lightning flash counters. The lightning flash counters having been described in literature up to now and developed for purely scientific applications operate in accordance with the following principle:

By means of a long-wire antenna of about 7 to 50 meters in length, the electromagnetic wave-trains resulting from a lightning flash discharge are received. The signal impulse originating from the lightning discharge supplies the input of an amplifier, in the output circuit of which there is a counter responding to the impulses received above a certain threshold value and counting them.

The disadvantages of the apparatuses applied in practical use up to now consist in the expensive mounting of the long-wire antenna, the insufliciency of selectivity especially when close to industrial establishments and the thereby existing susceptibility towards strewing-in radio frequency, and finally in the fact that the method does nothing but count the lightning flash discharges not allowing any conclusions as to intensity and period of time, and, moreover, the position of the counter read at any time does not give a meassure of the number of lightning flashes, but with permanent recording and the evaluation thereof.

It is one object of the present invention to provide an electronic device for indicating, registering and forecast ing local and distant thunderstorms which avoids those disadvantages and is based on a technical conception aiming at a simple setting or fixing of the device, at an elimination of foreign disturbances as far as possible, at a multiple evaluation of the lightning signals received, and at methods of indication allowing a direct reading of the degree of probability of thunderstorms.

With this and other objects in view which will become apparent in the following detailed description, the present invention, which is shown by example only will 3,465,245 Patented Sept. 2, 1969 ice be clearly understood in connection with the accompanying drawings, in which:

FIGURE 1 is a circuit diagram designed in accordance with the present invention;

FIG. 2 is a diagram indicating by symbols the increasing inclination to thunderstorms;

SIG. 3 is a schematic view indicating the intensity; an

FIG. 4 is a schematic view indicating the intensity in connection with a barograph.

Referring now to the drawings, and in particular to FIG. 1, shown by example, part of the frequency spectrum of the signal originating from the lightning flash discharge is received by a tuned antenna A. In conformity with the present state of scientific research the frequencies mostly appearing with the lightning flash discharge are in the ranges of about 0.5 to 30 kc./s. and 1 to 10 mc./s. As a selective antenna which can be tuned, in particular a ferrite rod antenna, there is especially a wavemagnet installed in a handy shape or, for instance, ro tatably mounted allowing to locate the center of a thunderstorm. After this preliminary selection by means of the antenna, the signal is amplified by a resonance amplifier V which allows a further suppression of disturbances caused by neighboring frequency ranges. Then, after a rectification by the stage GL, the signal is triple evaluated.

At first each impulse of direct current is integrated by a resistor-capacitor-(RC)-combination R C R 'C Hereby the capacitor C is charged to a voltage which is a measure of the total intensity, i.e., amplitude x period of time of the signals received, while the combination R 'C is for smoothing only. The discharging resistor R is proportioned in such a way that the time constant R C is much greater than the charging constant R C and of the order of 5 to 60 minutes. Hereby the store value during this time interval can be read at any time by means of a sensitive, series-connected to R instrument I, for the indication of current which allows to obtain a measure of the intensity of all lightning flash discharges picked up by the receiver during this period of time.

Simultaneously the received lightning flash discharges are counted, whereat the indication is not executed by a counting mechanism, however, since that meansaccording to what is stated aboveno direct information. On the contrary, the relay Rel is triggered by each impulse of direct current above a certain threshold value adjustable by R This relay Rel charges during the pulse duration the capacitor C to the battery voltage B. In the position of rest of the relay, the thereby received constant quantity of charge is released through the contact r and the resistor R to the storage capacitor C whereat C is much greater than C In this case the energy accumulated in C is directly a measure of the number of the lightning discharges received and is correspondingly indicated or recorded at the instrument J by way of a discharging resistor R whereat the time constant R C is equal to about 5 to 60 minutes, allowing to obtain here an information, as well as about a predetermined period of time.

Instead of the relay, it is possible to incorporate a monostable multivibrator which is triggered by the rectified impulse and which during the limited time of its excitation, charges the capacitor C by way of the resistor R2. I

Finally, the signals received are evaluated in relation to the period of time during which, for the duration of a time interval altogether, lightning troubles arise. For that purpose a thyristor Th is triggered by each impulse above a threshold value adjustable at the potentiometer P. Thereby, during the duration of the reception of the lightning signal, a constant charging current independent of the amplitude flows through the resistor R to the storage capacitor C By way of the smoothing combination R 'C and the resistor R the instrument J indicates a current which is a measure of the thereby defined total duration of lightning. Hereat the RC-combination is selected in such way that the time constant of the discharge, i.e., the period of time of measuring is of to 60 minutes.

The currents i i and i which are each-according to what is stated abovea measure of the lightning flash discharges picked up by the receiver during the past 5 to 60 minutes are indicated on scalesaccording to the example in FIG. 2-supplied with a graduation marked by growing figures and/or by symbols characterizing the increasing tendency to thunderstorms and/or by a widening wedge and/or by growing intensity in order to indicate the increasing tendency to thunderstorms.

In a simplified form the apparatus may exclusively be mounted either for the measuring of intensity, for counting, for measuring the period of time of lightning flash discharges or as a combination of two among these dimensions.

In an improved form the apparatus can be used for signalling and anticipatory warning in case of increased tendency to thunderstorms. For the purpose usual contact-instrument have been used for the instruments J J and J with the example according to FIG. 1 closing the contacts K K and K; at a certain threshold value and hereby releasing an optical and/or acoustical alarm, respectively, directly initiating a control action. It is important to notice the possibility of varying this threshold value because of the thereby existing individual adjustability of each apparatus, which can be adapted to peculiarities of the recaption conditions, to meteorological conditions, etc.

Instead of the RC-storage combination, other embodiments are available for the storage and indication of the intensity, number and/or duration of impulses by using a calorimeter, in which, as shown in the embodiment of FIG. 3, the impulses are fed to a heating coil HW, which is disposed in a gas-filled chamber I. In its unheated state in the chamber I and in a second, likewise gas-filled chamber II, which is connected with chamber I by means of a mercury filled capillary tube, the same temperature and the same pressure prevails. The heat energy fed to the heating coil HW by the impulses increases the temperature of the chamber I and displaces thereby the mercury thread QU in the direction toward the chamber II. By suitable provision of a heat insulation W1 of the chamber I, it is obtained, that the cooling and, thereby, the return of the mercury thread takes place likewise with the given time constant of about 5 to 60 minutes.

In the embodiment disclosed in FIG. 1, the supply of current is maintained from two series-connected 1.5 volt cells Z Z of a capacity of about 5 AH. Thereby the whole apparatus is independent of the main supply and therefore rather independent of all interferences, in particular disturbances caused by sparking, which may strew in through the mains supply. Moreover, in this form the apparatus is portable and, for instance, may be applied in the mountains and at sea, ranges of application where the forecast of thunderstorms is of special necessity.

If the limited capacity is disturbing, it is possible to transform the cells Z and Z into a rechargeable accumulator which, for instance, is perpetually charged by a photocell W on buffer battery operation; otherwise the apparatus is to be supplied from mains supply whereat sufficient filter-and-buffer-sections have to suppress a transmission of radio-frequency disturbances.

The apparatus being determined to indicate the tendency to thunderstorms and to predict thunderstorms to be expected at the point of observation, it is suitable and of importance for improving the probability of success, to couple further information with this apparatus. This is possible for instance, by combining the said apparatus with a barometer, which allows to observe the conditions characteristic of the formation of thunderstorms.

With the embodiment according to FIG. 1, in particular, the relay is formed in such a way, that it closes a circuit by means of its operating contact r at each counting of impulse and simultaneously writes a mark onto a barograph by means of a marking relay. Hereby a record of the atmospheric pressure is logically combined with a simultaneous record, written on the same tape, of the frequency of the number of lightnings.

Finally, another possibility presents itself for recording the number of lightning flashes on a conventional barograph, according to a method disclosed by example in FIG. 4.

A stepping motor of a step-by-step switch SM is triggered by each impulse. The stepping motor or the step-by-step switch carries a cam KS on its drive shaft KS. On the cam KS is disposed a writing bar SA rotatably mounted about a pivot DP and carrying at its tip end a writing pen F writing on a barograph drum ET. The cam KS is designed such that during a full revolution of the drive shaft KS the writing pen F performs an upward and downward recording movement. This movement can be performed by suitable design of the cam KS such, that the rotary angle of the drive shaft KS and the swinging angle of the writing bar SA are linearly proportional relative to each other. This arrangement permits a direct evaluation of the recording of the number of lightning discharges.

In order to provide for the user of the device for indication, recording and prognosis of close and far thunderstorms, as indicated in FIG. 1, by example, for the readiness for operation of the apparatus, a connection is provided from the auxiliary battery B, to the input of the rectifier by way of the resistor R and a pushbutton T. By repeated operation of the pushbutton T, it is possible to simulate impulses of direct current in a simple form, allowing to control the increase of the indications at the instruments J J and J With its various possibilities of use, the apparatus can be mounted either for stationary tasks as a wall or table set or for mobile operation as a portable pocket instrument.

We claim:

1. An electronic device for automatic indicating, registering and forecasting local and distant thunderstorms, wherein electromagnetic signals resulting from the lightning flash discharges, particularly in the frequency ranges of 0.3 to 30 kc./s. and of 1 to 10 mc./s., are received, comprising:

a selective antenna,

a resistance-capacitance- (RC) -section,

means for integrating impulses of direct current resulting from each lightning flash discharge into said resistance-capacitance-(RC)-section, to charge said capacitance to a voltage being a measure of the total intensity, comprising the product of amplitude with the period of time of signals received,

a first recording instrument,

a first, post-connected discharging resistor,

means for recording by said post-connected discharging resistor the total intensity of the direct current impulses stored in the RC-rnember by means of said recording instrument,

a first operating means excited by each of said impulses of direct curent above a predetermined threshold value,

means for counting each of said impulses of direct current,

a first capacitor,

a power source,

a second recording instrument,

a first attenuator,

a second resistor,

said operating means charging said first capacitor, in its operative position from said power source and supplying, in its inoperative position, said second recording instrument by said attenuator and said second resistor,

a second capacitor,

a thyristor triggered by each of said impulses of direct current and measuring the total duration of the lightning discharge, as well as charging said second capacitor,

a second attenuator,

a third resistor,

a third recording instrument, and

the accumulated charge being carried by means of said second attenuator, and said third resistor to said third recording instrument.

2. The device, as set forth in claim 1, wherein:

said selective antenna comprises a tuned wave magnet selectively amplified and rectified.

3. The device, as set forth in claim 1, wherein:

said selective antenna for the reception of signals of atmospheric origin is rotatably mounted, thereby permitting to locate the direction of a center of thunderstorms.

4. The device, as set forth in claim 1, wherein:

the period of time of accumulating each information amounts to about 5 to 60 minutes.

5. The device, as set forth in claim 1 wherein:

a signal is released at a predetermined threshold value of the intensity, number and total duration of the lightning flash discharges received, respectively.

6. The device, as set forth in claim 5, wherein:

said threshold values are variable allowing to adapt them to the special conditions at the point of observation, depending upon reception conditions and meteorological conditions.

7. The device, as set forth in claim 1, which includes a battery for operating said apparatus, and

5 11. The device, as set forth in claim 1, which includes:

a calorimeter including a vessel and adapted to measure the quantity of heat produced by the impulses in a heater spiral.

12. The device, as set forth in claim 11 wherein:

said vessel of said calorimeter is thermally insulated such, that the produced and indicated quantity of heat is kept accumulated for a time period of 5 to minutes.

13. The device, as set forth in claim 1, which includes:

a stepping motor,

a writing pen mounted in a swinging bar, and

a cam turned by said stepping motor and controlling the movement of said writing pen.

14. The device, as set forth in claim 13, which includes:

a barographdrum receiving the recording by an upward-downWard-movement of said Writing pen.

15. The device, as set forth in claim 13, wherein:

said cam has a curvature such that the angle of swinging of said writing pen is proportional to the number of lightning flashes.

16. The device, as set forth in claim 1, which includes:

a scale supplied with symbols characteristic of thunderstorms and marked by a wedge and growing intensity, and

said scale indicating the measured intensity, number and duration of the lightning discharges, in order to indicate the increasing probability of the formation of a thunderstorm.

17. The apparatus for indicating, recording and predicting local and distant thunderstorms, as set forth in claim 1, wherein said operating means comprises a monostable multivibrator, and the latter, during the time of its own excitation charges a third capacitor by means of a fourth resistor.

18. The apparatus for indicating, recording and predicting local and distant thunderstorms, as set forth in claim 1, wherein said operating means comprises a relay.

References Cited Proceedings of the IEEE, A Transistorized Radiation-Field-Actuated Lightning Flash Counter (B.S. Sonde), November 1963, pages 1501-1506.

RUDOLPH V. ROLINEC, Primary Examiner E. L. STOLARUN, Assistant Examiner U.S. Cl. X.R.

my UNI ED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. Dated September 2, 1969 Inventor) Heinz-Jfirgen Fischer and Walter Schmidt It; is certified that: error appears in the above-1dencif1ed, pacnt and that said Letters Patent are hereby correctedda ahcwn Below: T

In the heading of the petent specification, line 10 for "A SL124; Oct. 12, 1966, A 53, 799" read A 51, 124;Oct. 17, 1966, A 53, 799

SI'GN'ED AND SEALED AUG 4 .197

Y (SEAL) Anew Edw'ard M. Fletcher, 3r. 35i E- SGHUYLER, JR. Attesting Officer commissionei Of Patents 

